Typically you have those applications you like and those applications you love to use but every now and then an application comes around that completely changes the way you work and those become the applications you can't live without. For me, that application is Quicksilver from Blacktree on my OSX machine. Not sure exactly how to describe what exactly Quicksilver is. To say it's just an "application launcher" would be seriously underminding everything Quicksilver brings to the table.
It took me sometime to get my mind around what Quicksilver was and what it could do. I am probably a yellow belt when it comes to using Quicksilver; I am well beyond using the basic features but still haven't really scratched the surface of what it can do to really master it. I use a similar application for Linux called Gnome Do and one for my Windows boxes called Launchy but neither of them have the integration and do for me what Quicksilver does. Even the Apple OS X built in Spotlight falls far short in my opinion.
Quicksilver can be a tough application to understand and I personally hadn't come across a lot of good instructions on how to use it. Been doing the whole trial by fire approach. But fortunately one of my buddies over at Splunk has put together one of the best Quicksilver tutorials I've seen to date. Check out Michael Wilde's Blog entry on "Mac Productivity with Quicksilver"
